| #!/usr/bin/env python3 |
| # Copyright 2022 Canonical Ltd. |
| # |
| # Licensed under the Apache License, Version 2.0 (the "License"); you may |
| # not use this file except in compliance with the License. You may obtain |
| # a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| # License for the specific language governing permissions and limitations |
| # under the License. |
| # |
| # For those usages not covered by the Apache License, Version 2.0 please |
| # contact: legal@canonical.com |
| # |
| # To get in touch with the maintainers, please contact: |
| # osm-charmers@lists.launchpad.net |
| # |
| # |
| # Learn more at: https://juju.is/docs/sdk |
| |
| """Juju simpletreams charm.""" |
| |
| import logging |
| import subprocess |
| from dataclasses import dataclass |
| from pathlib import Path |
| from typing import Any, Dict |
| |
| from charms.nginx_ingress_integrator.v0.ingress import IngressRequires |
| from charms.observability_libs.v1.kubernetes_service_patch import KubernetesServicePatch |
| from charms.osm_libs.v0.utils import ( |
| CharmError, |
| check_container_ready, |
| check_service_active, |
| ) |
| from lightkube.models.core_v1 import ServicePort |
| from ops.charm import ActionEvent, CharmBase |
| from ops.main import main |
| from ops.model import ActiveStatus, Container |
| |
| SERVICE_PORT = 8080 |
| |
| logger = logging.getLogger(__name__) |
| container_name = "server" |
| |
| |
| @dataclass |
| class ImageMetadata: |
| """Image Metadata.""" |
| |
| region: str |
| auth_url: str |
| image_id: str |
| series: str |
| |
| |
| class JujuSimplestreamsCharm(CharmBase): |
| """Simplestreams Kubernetes sidecar charm.""" |
| |
| def __init__(self, *args): |
| super().__init__(*args) |
| self.ingress = IngressRequires( |
| self, |
| { |
| "service-hostname": self.external_hostname, |
| "service-name": self.app.name, |
| "service-port": SERVICE_PORT, |
| }, |
| ) |
| event_handler_mapping = { |
| # Core lifecycle events |
| self.on["server"].pebble_ready: self._on_server_pebble_ready, |
| self.on.update_status: self._on_update_status, |
| self.on["peer"].relation_changed: self._push_image_metadata_from_relation, |
| # Action events |
| self.on["add-image-metadata"].action: self._on_add_image_metadata_action, |
| } |
| |
| for event, handler in event_handler_mapping.items(): |
| self.framework.observe(event, handler) |
| |
| port = ServicePort(SERVICE_PORT, name=f"{self.app.name}") |
| self.service_patcher = KubernetesServicePatch(self, [port]) |
| self.container: Container = self.unit.get_container(container_name) |
| self.unit.set_workload_version(self.unit.name) |
| |
| @property |
| def external_hostname(self) -> str: |
| """External hostname property. |
| |
| Returns: |
| str: the external hostname from config. |
| If not set, return the ClusterIP service name. |
| """ |
| return self.config.get("external-hostname") or self.app.name |
| |
| # --------------------------------------------------------------------------- |
| # Handlers for Charm Events |
| # --------------------------------------------------------------------------- |
| |
| def _on_server_pebble_ready(self, _) -> None: |
| """Handler for the config-changed event.""" |
| try: |
| self._push_configuration() |
| self._configure_service() |
| self._push_image_metadata_from_relation() |
| # Update charm status |
| self._on_update_status() |
| except CharmError as e: |
| logger.debug(e.message) |
| self.unit.status = e.status |
| |
| def _on_update_status(self, _=None) -> None: |
| """Handler for the update-status event.""" |
| try: |
| check_container_ready(self.container) |
| check_service_active(self.container, container_name) |
| self.unit.status = ActiveStatus() |
| except CharmError as e: |
| logger.debug(e.message) |
| self.unit.status = e.status |
| |
| def _push_image_metadata_from_relation(self, _=None): |
| subprocess.run(["rm", "-rf", "/tmp/simplestreams"]) |
| subprocess.run(["mkdir", "-p", "/tmp/simplestreams"]) |
| image_metadata_dict = self._get_image_metadata_from_relation() |
| for image_metadata in image_metadata_dict.values(): |
| subprocess.run( |
| [ |
| "files/juju-metadata", |
| "generate-image", |
| "-d", |
| "/tmp/simplestreams", |
| "-i", |
| image_metadata.image_id, |
| "-s", |
| image_metadata.series, |
| "-r", |
| image_metadata.region, |
| "-u", |
| image_metadata.auth_url, |
| ] |
| ) |
| subprocess.run(["chmod", "555", "-R", "/tmp/simplestreams"]) |
| self.container.push_path("/tmp/simplestreams", "/app/static") |
| |
| def _on_add_image_metadata_action(self, event: ActionEvent): |
| relation = self.model.get_relation("peer") |
| try: |
| if not relation: |
| raise Exception("charm has not been fully initialized. Try again later.") |
| if not self.unit.is_leader(): |
| raise Exception("I am not the leader!") |
| if any( |
| prohibited_char in param_value |
| for prohibited_char in ",; " |
| for param_value in event.params.values() |
| ): |
| event.fail("invalid params") |
| return |
| |
| image_metadata_dict = self._get_image_metadata_from_relation() |
| |
| new_image_metadata = ImageMetadata( |
| region=event.params["region"], |
| auth_url=event.params["auth-url"], |
| image_id=event.params["image-id"], |
| series=event.params["series"], |
| ) |
| |
| image_metadata_dict[event.params["image-id"]] = new_image_metadata |
| |
| new_relation_data = [] |
| for image_metadata in image_metadata_dict.values(): |
| new_relation_data.append( |
| f"{image_metadata.image_id};{image_metadata.series};{image_metadata.region};{image_metadata.auth_url}" |
| ) |
| relation.data[self.app]["data"] = ",".join(new_relation_data) |
| except Exception as e: |
| event.fail(f"Action failed: {e}") |
| logger.error(f"Action failed: {e}") |
| |
| # --------------------------------------------------------------------------- |
| # Validation and configuration and more |
| # --------------------------------------------------------------------------- |
| |
| def _get_image_metadata_from_relation(self) -> Dict[str, ImageMetadata]: |
| if not (relation := self.model.get_relation("peer")): |
| return {} |
| |
| image_metadata_dict: Dict[str, ImageMetadata] = {} |
| |
| relation_data = relation.data[self.app].get("data", "") |
| if relation_data: |
| for image_metadata_string in relation_data.split(","): |
| image_id, series, region, auth_url = image_metadata_string.split(";") |
| image_metadata_dict[image_id] = ImageMetadata( |
| region=region, |
| auth_url=auth_url, |
| image_id=image_id, |
| series=series, |
| ) |
| |
| return image_metadata_dict |
| |
| def _configure_service(self) -> None: |
| """Add Pebble layer with the ro service.""" |
| logger.debug(f"configuring {self.app.name} service") |
| self.container.add_layer(container_name, self._get_layer(), combine=True) |
| self.container.replan() |
| |
| def _push_configuration(self) -> None: |
| """Push nginx configuration to the container.""" |
| self.container.push("/etc/nginx/nginx.conf", Path("files/nginx.conf").read_text()) |
| self.container.make_dir("/app/static", make_parents=True) |
| |
| def _update_ingress_config(self) -> None: |
| """Update ingress config in relation.""" |
| ingress_config = { |
| "service-hostname": self.external_hostname, |
| "max-body-size": self.config["max-body-size"], |
| } |
| if "tls-secret-name" in self.config: |
| ingress_config["tls-secret-name"] = self.config["tls-secret-name"] |
| logger.debug(f"updating ingress-config: {ingress_config}") |
| self.ingress.update_config(ingress_config) |
| |
| def _get_layer(self) -> Dict[str, Any]: |
| """Get layer for Pebble.""" |
| return { |
| "summary": "server layer", |
| "description": "pebble config layer for server", |
| "services": { |
| container_name: { |
| "override": "replace", |
| "summary": "server service", |
| "command": 'nginx -g "daemon off;"', |
| "startup": "enabled", |
| } |
| }, |
| } |
| |
| |
| if __name__ == "__main__": # pragma: no cover |
| main(JujuSimplestreamsCharm) |